U.S. patent number 8,171,993 [Application Number 12/842,738] was granted by the patent office on 2012-05-08 for water heating apparatus for continuous heated water flow and method for use in hydraulic fracturing.
This patent grant is currently assigned to Heat On-The-Fly, LLC. Invention is credited to Ransom Mark Hefley.
United States Patent |
8,171,993 |
Hefley |
May 8, 2012 |
**Please see images for:
( Reexamination Certificate ) ** |
Water heating apparatus for continuous heated water flow and method
for use in hydraulic fracturing
Abstract
A method of hydraulic fracturing of an oil producing formation
includes the provision of a heating apparatus which is
transportable and that has a vessel for containing water. A water
stream of cool or cold water is transmitted from a source to a
mixer, the cool or cold water stream being at ambient temperature.
The mixer has an inlet that receives cool or cold water from the
source and an outlet that enables a discharge of a mix of cool or
cold water and the hot water. After mixing in the mixer, the water
assumes a temperature that is suitable for mixing with chemicals
that are used in the fracturing process, such as a temperature of
about 40.degree. -120.degree. F.+(4.4 - 48.9.degree. C.+). An
outlet discharges a mix of the cool and hot water to surge tanks or
to mixing tanks. In the mixing tanks, a proppant and an optional
selected chemical or chemicals are added to the water which has
been warmed. From the mixing tanks, the water with proppant and
optional chemicals is injected into the well for part of the
hydraulic fracturing operation.
Inventors: |
Hefley; Ransom Mark (Elk City,
OK) |
Assignee: |
Heat On-The-Fly, LLC
(Covington, LA)
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Family
ID: |
43123794 |
Appl.
No.: |
12/842,738 |
Filed: |
July 23, 2010 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20100294494 A1 |
Nov 25, 2010 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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61297097 |
Jan 21, 2010 |
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61254122 |
Oct 22, 2009 |
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61276950 |
Sep 18, 2009 |
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Current U.S.
Class: |
166/303;
166/305.1; 166/57; 166/302; 366/167.1; 166/308.1 |
Current CPC
Class: |
E21B
43/267 (20130101); E21B 43/26 (20130101); F24H
1/125 (20130101); G05D 23/1306 (20130101) |
Current International
Class: |
E21B
43/24 (20060101) |
Field of
Search: |
;166/302,303,305.1,308.1,57 ;285/125.1,129.1,130.1
;366/167.1,173.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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WO 2010-018356 |
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Feb 2010 |
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WO |
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Primary Examiner: Thompson; Kenneth L
Assistant Examiner: Gottlieb; Elizabeth
Attorney, Agent or Firm: Garvey, Smith, Nehrbass &
North, L.L.C. Nehrbass; Seth M. Brignac; Len R.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
Incorporated herein by reference are my prior U.S. provisional
patent application No. 61/297,097, filed 21 Jan. 2010, my prior
U.S. provisional patent application no. 61/254,122, filed 22 Oct.
2009, and my prior U.S. provisional patent application No.
61/276,950, filed 18 Sep. 2009. Priority of these applications is
hereby claimed.
Claims
The invention claimed is:
1. A method of fracturing a formation producing at least one of oil
and gas, comprising the steps of: a) providing a transportable
heating apparatus for heating water to a temperature of at least
about 40 degrees F. (4.4 degrees C.); b) transmitting a water
stream of cool or cold water to a mixer, the cool or cold water
stream being at a temperature of less than a predetermined target
temperature; c) the mixer having a first inlet that receives cool
or cold water from the stream of step "b" and a first outlet that
enables discharge of a substantially continuous stream which is a
mix of cool or cold and heated water; d) the mixer having a second
inlet that enables heated water to enter the mixer; e) adding
heated water from the transportable heating apparatus of step "a"
to the mixer via the second inlet; f) wherein the volume of cool or
cold water of step "b" is much greater than the volume of heated
water of step "e"; g) adding a selected proppant to the mix of cool
or cold and heated water discharged from the mixer after step "f";
and h) transmitting the mix of cool or cold and heated water and
the proppant into a formation producing at least one of oil and
gas, wherein water flows substantially continuously from the first
inlet to the first outlet during the fracturing process.
2. The method of claim 1 wherein the mixer has a tubular body with
a bore.
3. The method of claim 2 wherein the tubular body bore has a
central longitudinal axis and in step "e" the heated water enters
the mixer bore at an angle.
4. The method of claim 1 wherein the heated water and the cool or
cold water mix in step "e" with turbulent flow.
5. The method of claim 1 wherein the transportable heating
apparatus is a wheeled vehicle.
6. The method of claim 1 wherein the cool or cold water stream has
a temperature of between about 33 and 80 degrees F. (0.6 and 27
degrees C.).
7. The method of claim 1 wherein the stream of cool or cold water
has a temperature of above freezing.
8. The method of claim 1 wherein in step "e" the heated water has a
temperature of between about 40 and 120 degrees F. (4.4 and 48.9
degrees C.).
9. The method of claim 1 wherein in step "e" the heated water has a
temperature of between about 40 and 150 degrees F. (4.4 and 65.6
degrees C.).
10. The method of claim 1 wherein in step "e" the heated water has
a temperature of between about 40 and 200 degrees F. (4.4 and 93.3
degrees C.).
11. The method of claim 1 wherein there are two mixers connected
together in series in steps "b" through "e".
12. The method of claim 1 further comprising adding chemicals to
the mix of cool or cold and heated water during step "g".
13. A method of fracturing a formation producing at least one of
oil and gas, comprising the steps of: a) providing a transportable
heating apparatus that heats water to a temperature of at least 40
degrees F. (4.4 degrees C.); b) transmitting a water stream of cool
or cold water to a mixer, the cool or cold water stream being at a
temperature of less than a predetermined target temperature; c) the
mixer having a first inlet that receives cool or cold water from
the source of step "b" and a first outlet that enables discharge of
a substantially continuous stream which is a mix of cool or cold
water and heated water; d) the mixer having a second outlet and a
second inlet downstream of the second outlet; e) adding heated
water from the transportable heating apparatus of step "a" to the
mixer via the second inlet; f) continuously transmitting water from
the mixer via the second outlet to the heating apparatus of step
"a"; g) wherein the volume of cool or cold water of step "b" is
much greater than the volume of heated water of step "e"; h) adding
a selected proppant to the mix of cool or cold water and heated
water discharged from the first outlet of the mixer after step "f";
and i) transmitting the mix of cool or cold water and heated water
and the proppant into a formation producing at least one of oil and
gas, wherein water flows substantially continuously from the first
inlet to the first outlet during the fracturing process.
14. The method of claim 13 wherein the mixer has a tubular body
with a bore.
15. The method of claim 14 wherein the tubular body bore has a
central longitudinal axis and in step "e" the heated water enters
the mixer bore at an angle.
16. The method of claim 14 wherein the tubular body bore has a
central longitudinal axis and in step "f" the water discharges from
the mixer bore at an angle.
17. The method of claim 13 wherein the heated water and the cool or
cold water mix in step "e" with turbulent flow.
18. The method of claim 13 wherein the transportable heating
apparatus is a wheeled vehicle.
19. The method of claim 13 wherein the cool or cold water stream
has a temperature of between about 33 and 80 degrees F. (0.6 and 27
degrees C.).
20. The method of claim 13 wherein in step "e" the heated water has
a temperature of between about 40 and 200 degrees F. (4.4 and 93.3
degrees C.).
21. The method of claim 13 wherein in step "e" the heated water has
a temperature of between about 40 and 150 degrees F. (4.4 and 65.6
degrees C.).
22. The method of claim 13 wherein in step "e" the heated water has
a temperature of between about 40 and 120 degrees F. (4.4 and 48.9
degrees C.).
23. The method of claim 13 wherein there are two mixers connected
together in series in step "b" through "e".
24. The method of claim 13 wherein there are two mixers connected
together in parallel in step "b" through "e".
25. The method of claim 13 further comprising adding chemicals to
the mix of cool or cold water and heated water during step "h".
26. An oil well hydraulic fracturing system, comprising: a) a
transportable heating apparatus that heats water to a temperature
of at least 40 degrees F. (4.4 degrees C.); b) a source of cool or
cold water at about ambient temperature; c) a mixer having a first
inlet and a first outlet; d) a second inlet that enables heated
water to enter the mixer; e) a second outlet that enables removal
of water from the mixer upstream of the second inlet; f) a first
flowline that transmits heated water between the heater and the
second inlet; g) a second flowline that transmits water between the
second outlet and the heater, the second flowline being upstream of
the second inlet; and h) a mixing tank that is receptive of a flow
of a mix of cool or cold and heated water from the mixer, said tank
enabling a proppant to be mixed with the mix of cool or cold and
heated water that is discharged from the first outlet.
27. The oil well hydraulic fracturing system of claim 26 wherein
the mixer has a tubular body.
28. The oil well hydraulic fracturing system of claim 27 wherein
the tubular body has a central longitudinal axis and heated water
enters the mixer at an angle via the second inlet.
29. The oil well hydraulic fracturing system of claim 27 wherein
the tubular body has a central longitudinal axis and water
discharges from the mixer at an angle via the second outlet.
30. The oil well hydraulic fracturing system of claim 26 wherein
the mixer is configured to mix heated water and cool or cold water
with turbulent flow downstream of second outlet.
31. The oil well hydraulic fracturing system of claim 26 wherein
the heating apparatus is a wheeled vehicle.
32. The oil well hydraulic fracturing system of claim 26 wherein
the source of cool or cold water has a temperature of between about
33 and 80 degrees F. (0.6 and 27 degrees C.).
33. The oil well hydraulic fracturing system of claim 26 wherein
the heated water in the first flowline has a temperature of between
about 120 and 240 degrees F. (48.9 and 116 degrees C.).
34. The oil well hydraulic fracturing system of claim 26 wherein
the mixer is connected in series with a second mixer so that the
mix of cool or cold and heated water discharged from the first
outlet is transmitted to the second mixer.
35. The oil well hydraulic fracturing system of claim 26 wherein
the mixing tank also enables chemicals to be mixed with the mix of
cool or cold and heated water.
36. A hydraulic fracturing apparatus, comprising: a) a heating
apparatus for heating water to a temperature of at least 40 degrees
F. (4.4 degrees C.) to produce heated water; b) a source of cool or
cold water; c) a mixer having a first inlet that receives cool or
cold water from the source of cool or cold water and a first outlet
that enables discharge of a mix of cool or cold and heated water;
d) the mixer having a second outlet and a second inlet spaced
downstream of the second outlet; e) a first flowline that transmits
heated water from the heating apparatus to the mixer via the second
inlet; f) a second flowline that transmits water from the mixer to
the heating apparatus via the second outlet; g) a tank that enables
a selected proppant to be mixed with the mix of cool or cold and
heated water that is discharged from the first outlet of the mixer;
h) a flowline that connects the mixer with the tank; i) a flowline
that transmits the mix of cool or cold and heated water and
proppant from the tank into a formation producing at least one of
oil and gas.
37. The hydraulic fracturing apparatus of claim 36 wherein the
mixer has a tubular body.
38. The hydraulic fracturing apparatus of claim 37 wherein the
tubular body has a central longitudinal axis and the heated water
enters the mixer at an angle.
39. The hydraulic fracturing apparatus of claim 37 wherein the
tubular body has a central longitudinal axis and cool or cold water
discharges from the mixer through the second outlet at an acute
angle with respect to said axis.
40. The hydraulic fracturing apparatus of claim 36 wherein the
heated water and the cool or cold water from the source of water
mix with turbulent flow in the mixer.
41. The hydraulic fracturing apparatus of claim 36 wherein the
heating apparatus is a wheeled vehicle.
42. The hydraulic fracturing apparatus of claim 36 wherein the cool
or cold water source has a temperature of between about 33 and 80
degrees F. (0.6 and 27 degrees C.).
43. The hydraulic fracturing apparatus of claim 36 wherein the
heated water in the first flowline has a temperature of between
about 120 and 240 degrees F. (48.9 and 116 degrees C.).
44. The hydraulic fracturing apparatus of claim 36 wherein there
are two or more mixers connected together in series.
45. The hydraulic fracturing apparatus of claim 36 wherein there
are two or more mixers connected together in parallel.
46. The hydraulic fracturing apparatus of claim 36 wherein the
volume of heated water flowing in the first flowline is smaller
than the volume of water flowing in the mixer.
47. The hydraulic fracturing apparatus of claim 36 wherein the
volume of heated water flowing in the first flowline is less than
half the volume of water flowing in the mixer.
48. The hydraulic fracturing apparatus of claim 36 wherein the
volume of heated water flowing in the first flowline is less than
ten percent the volume of cool or cold water flowing in the first
inlet.
49. The hydraulic fracturing apparatus of claim 36 wherein the tank
also enables chemicals to be mixed with the mix of cool or cold and
heated water.
50. A method of fracturing a formation producing at least one of
oil and gas, comprising the steps of: a) providing a transportable
heating apparatus for heating water to a temperature of at least
about 40 degrees F. (4.4 degrees C.); b) transmitting a water
stream of cool or cold water to a mixer, the cool or cold water
stream being at a temperature of less than a predetermined target
temperature; c) the mixer having an inlet that receives cool or
cold water from the stream of step "b" and an outlet that enables
discharge of a substantially continuous stream which is a mix of
cool or cold and heated water; d) the mixer having a lateral inlet
fitting that enables heated water to enter a mixer bore at an
angle; e) adding heated water from the transportable heating
apparatus of step "a" to the mixer via the lateral inlet fitting;
f) wherein the volume of cool or cold water of step "b" is much
greater than the volume of heated water of step "e"; g) adding a
selected proppant to the mix of cool or cold and heated water
discharged from the outlet of the mixer after step "f"; and h)
transmitting the mix of cool or cold and heated water and the
proppant into a formation producing at least one of oil and gas,
wherein water flows substantially continuously from the inlet to
the outlet during the fracturing process.
51. The method of claim 50 wherein the mixer has a tubular body
with a bore, one end of the bore being the mixer inlet and the
other end of the bore being the mixer outlet.
52. The method of claim 51 wherein the tubular body bore has a
central longitudinal axis and in step "e" the heated water enters
the mixer bore at an acute angle.
53. The method of claim 51 wherein the tubular body bore has a
central longitudinal axis and in step "f" the water discharges from
the mixer bore at an acute angle.
54. The method of claim 50 wherein the heated water and the cool or
cold water mix in step "e" with turbulent flow.
55. The method of claim 50 wherein the transportable heating
apparatus is a wheeled vehicle.
56. The method of claim 50 wherein the cool or cold water stream
has a temperature of between about 33 and 80 degrees F. (0.6 and 27
degrees C.).
57. The method of claim 50 wherein the cool or cold water stream
has a temperature of above freezing.
58. The method of claim 50 wherein in step "e" the heated water has
a temperature of between about 40 and 120 degrees F. (4.4 and 48.9
degrees C.).
59. The method of claim 50 wherein in step "e" the heated water has
a temperature of between about 40 and 150 degrees F. (4.4 and 65.6
degrees C.).
60. The method of claim 50 wherein in step "e" the heated water has
a temperature of between about 40 and 200 degrees F. (4.4 and 93.3
degrees C.).
61. The method of claim 50 wherein there are two mixers connected
together in series in step "b" through "e".
62. The method of claim 50 further comprising adding chemicals to
the mix of cool or cold and heated water during step "g".
63. A method of fracturing a formation producing at least one of
oil and gas, comprising the steps of: a) providing a transportable
heating apparatus that heats water to a temperature of at least 40
degrees F. (4.4 degrees C.); b) transmitting a water stream of cool
or cold water to a mixer, the cool or cold water stream being at a
temperature of less than a predetermined target temperature; c) the
mixer having an inlet that receives cool or cold water from the
cool or cold water stream of step "b" and an outlet that enables
discharge of a substantially continuous stream which is a mix of
cool or cold and heated water; d) the mixer having a first lateral
inlet fitting and a second lateral inlet fitting downstream of the
first lateral inlet fitting; e) adding heated water from the
transportable heating apparatus of step "a" to the mixer via the
second lateral inlet fitting; f) continuously transmitting water
from the mixer via the first lateral inlet fitting to the heating
apparatus of step "a"; g) wherein the volume of cool or cold water
of step "b" is much greater than the volume of heated water of step
"e"; h) adding a selected proppant to the mix of cool or cold and
heated water discharged from the outlet of the mixer after step
"f"; and i) transmitting the mix of cool or cold and heated water
and the proppant into a formation producing at least one of oil and
gas, wherein water flows substantially continuously from the inlet
to the outlet during the fracturing process.
64. The method of claim 63 wherein the mixer has a tubular body
with a bore, one end of the bore being the mixer inlet and the
other end of the bore being the mixer outlet.
65. The method of claim 64 wherein the tubular body bore has a
central longitudinal axis and in step "e" the heated water enters
the mixer bore at an acute angle.
66. The method of claim 64 wherein the tubular body bore has a
central longitudinal axis and in step "f" the water discharges from
the mixer bore at an acute angle.
67. The method of claim 63 wherein the heated water and the cool or
cold water mix in step "e" with turbulent flow.
68. The method of claim 63 wherein the transportable heating
apparatus is a wheeled vehicle.
69. The method of claim 63 wherein the cool or cold water stream
has a temperature of between about 33 and 80 degrees F. (0.6 and 27
degrees C.).
70. The method of claim 63 wherein in step "e" the heated water has
a temperature of between about 40 and 200 degrees F. (4.4 and 93.3
degrees C.).
71. The method of claim 63 wherein in step "e" the heated water has
a temperature of between about 40 and 150 degrees F. (4.4 and 65.6
degrees C.).
72. The method of claim 63 wherein in step "e" the heated water has
a temperature of between about 40 and 120 degrees F. (4.4 and 48.9
degrees C.).
73. The method of claim 63 wherein there are two mixers connected
together in series in step "b" through "e".
74. The method of claim 63 wherein there are two mixers connected
together in parallel in step "b" through "e".
75. The method of claim 63 further comprising adding chemicals to
the mix of cool or cold and heated water during step "h".
76. An oil well hydraulic fracturing system, comprising: a) a
transportable heating apparatus that heats water to a temperature
of at least 40 degrees F. (4.4 degrees C.); b) a source of cool or
cold water at about ambient temperature; c) a mixer having an
inlet, an outlet and a mixer bore that extends between the inlet
and the outlet; d) a first lateral fitting on the mixer that
enables heated water to enter the mixer bore; e) a second lateral
fitting on the mixer that enables removal of water from the mixer
bore upstream of the first lateral fitting and wherein at least one
of the lateral fittings has a wall portion that extends into the
mixer bore; f) a first flowline that transmits heated water between
the heater and the first lateral fitting; g) a second flowline that
transmits water between the second lateral fitting and the heater,
the second flowline being upstream of the first lateral fitting;
and h) a mixing tank that is receptive of a flow of a mix of cool
or cold and heated water from the bore of the mixer, said tank
enabling a proppant to be mixed with the mix of cool or cold and
heated water that is discharged from the mixer outlet.
77. The oil well hydraulic fracturing system of claim 76 wherein
the mixer has a tubular body with a bore, one end of the bore being
the mixer inlet and the other end of the bore being the mixer
outlet.
78. The oil well hydraulic fracturing system of claim 77 wherein
the tubular body bore has a central longitudinal axis and heated
water enters the mixer bore at an acute angle via the first lateral
fitting.
79. The oil well hydraulic fracturing system of claim 77 wherein
the tubular body bore has a central longitudinal axis and water
discharges from the mixer bore at an acute angle via the second
lateral fitting.
80. The oil well hydraulic fracturing system of claim 76 wherein
the mixer is configured to mix heated water and cool or cold water
with turbulent flow downstream of one of the lateral fittings.
81. The oil well hydraulic fracturing system of claim 76 wherein
the heating apparatus is a wheeled vehicle.
82. The oil well hydraulic fracturing system of claim 76 wherein
the source of water has a temperature of between about 33 and 80
degrees F. (0.6 and 27 degrees C.).
83. The oil well hydraulic fracturing system of claim 76 wherein
the heated water in the first flowline has a temperature of between
about 120 and 240 degrees F. (48.9 and 116 degrees C.).
84. The oil well hydraulic fracturing system of claim 76 wherein
the mixer is connected in series with a second mixer so that the
mix of cool or cold and heated water discharged from the first
mixer outlet is transmitted to the second mixer.
85. The oil well hydraulic fracturing system of claim 76 wherein
the mixing tank also enables chemicals to be mixed with the mix of
cool or cold and heated water.
86. A hydraulic fracturing apparatus, comprising: a) a heating
apparatus for heating water to a temperature of at least 40 degrees
F. (4.4 degrees C.); b) a source of cool or cold water; c) a mixer
having an inlet that receives cool or cold water from the source of
cool or cold water and an outlet that enables discharge of a mix of
cool or cold and heated water; d) the mixer having a first lateral
inlet fitting and a second lateral inlet fitting spaced downstream
of the first lateral inlet fitting; e) a first flowline that
transmits heated water from the heating apparatus to the mixer via
the second lateral inlet fitting; f) a second flowline that
transmits water from the mixer to the heating apparatus via the
first lateral inlet fitting; g) a tank that enables a selected
proppant to be mixed with the mix of cool or cold and heated water
that is discharged from the outlet of the mixer; h) a flowline that
connects the mixer bore with the tank; i) a flowline that transmits
the mix of cool or cold and heated water and proppant from the tank
into a formation producing at least one of oil and gas.
87. The hydraulic fracturing apparatus of claim 86 wherein the
mixer has a tubular body with a bore, one end of the bore being the
mixer inlet and the other end of the bore being the mixer
outlet.
88. The hydraulic fracturing apparatus of claim 87 wherein the
tubular body bore has a central longitudinal axis and the heated
water enters the mixer bore at an acute angle.
89. The hydraulic fracturing apparatus of claim 87 wherein the
tubular body bore has a central longitudinal axis and water
discharges from the mixer bore via the first lateral inlet fitting
at an acute angle with respect to said axis.
90. The hydraulic fracturing apparatus of claim 86 wherein the
heated water and the cool or cold water from the source of cool or
cold water mix with turbulent flow in the mixer bore.
91. The hydraulic fracturing apparatus of claim 86 wherein the
heating apparatus is a wheeled vehicle.
92. The hydraulic fracturing apparatus of claim 86 wherein the cool
or cold water source has a temperature of between about 33 and 80
degrees F.(0.6 and 27 degrees C.).
93. The hydraulic fracturing apparatus of claim 86 wherein the
heated water in the first flowline has a temperature of between
about 120 and 240 degrees F. (48.9 and 116 degrees C.).
94. The hydraulic fracturing apparatus of claim 86 wherein there
are two or more mixers connected together in series.
95. The hydraulic fracturing apparatus of claim 86 wherein there
are two or more mixers connected together in parallel.
96. The hydraulic fracturing apparatus of claim 86 wherein the
volume of heated water flowing in the first flowline is smaller
than the volume of water flowing in the mixer bore.
97. The hydraulic fracturing apparatus of claim 86 wherein the
volume of heated water flowing in the first flowline is less than
half the volume of water flowing in the mixer bore.
98. The hydraulic fracturing apparatus of claim 86 wherein the
volume of heated water flowing in the first flowline is less than
ten percent the volume of water flowing in the mixer bore.
99. The hydraulic fracturing apparatus of claim 86 wherein the tank
also enables chemicals to be mixed with the mix of cool or cold and
heated water.
Description
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable
REFERENCE TO A "MICROFICHE APPENDIX"
Not applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method and apparatus for the
continuous preparation of heated water flow for use in hydraulic
fracturing.
2. General Background of the Invention In connection with
production of oil or gas from a geological formation, the
production may have a poor flow rate due to low permeability or
from damage or clogging of the formation during drilling
particularly in formations of tight sands with low porosity and oil
& gas shales. Hydraulic fracturing also known as "fracing" is a
process employed after the well has been drilled, for the
completion of the well to enhance hydrocarbon production.
Hydraulic fracturing creates porosity by fracturing the formations
surrounding the wellbore. These fractures allow the oil or gas to
flow more easily from the tight sands or shales to the production
well. The common method to create fractures in the formation is to
pump a mixture of water, chemicals and sands into the rock or
formation. When the pumped fluid mixture reaches sufficient
pressures, the formation will fracture, creating the permeability
required to release the captured hydrocarbons.
Hydraulic fracturing generally entails injecting fluid into the
wellbore at a sufficient rate and pressure to overcome the tensile
strength of the formation creating cracks or fractures extending
from the wellbore. U.S. Pat. Nos. 3,816,151, 3,938,594 and
4,137,182 (each hereby incorporated herein by reference) relate to
hydraulic fracturing processes using various fracturing fluids.
Also incorporated herein by reference are the following US Patent
document no: 2008/0029267; U.S. Pat. Nos. 5,979,549; 5,586,720;
5,183,029; 5,038,853; 4,518,568; 4,076,628; 2,631,017; 2,486,141;
2,395,258; 2,122,900; 2,065,789.
One of the key elements of the fracturing fluid is water, which is
the carrying fluid for the proppant (and optional appropriate
chemical mix) required for the process. The proppant holds open the
fractures and provides porosity to allow hydrocarbons to flow out
of the formation. Before the fracing fluid is injected into the
well, the water is normally heated to the target temperature (e.g.,
40.degree. F. to 120.degree. F.+ (4.4.degree. C. to 48.9.degree.
C.+)), which depends on the geologic formation and chemicals used,
for example, typically 65.degree. F.-75.degree. F. (18.degree.
C.-24.degree. C.) in the Bakken Shale located in North Dakota,
Montana, and southern Canada) in order to achieve the proper
chemical mix required for each particular hydraulic fracturing
operation. A further result of heating the water prior to mixing
with chemicals is the reduction of amount of chemicals that may be
required for the hydraulic fracturing operation. In addition, a
lower density of the heated water reduces the pressure on the pipes
and connections and thereby reduces the risk for mechanical
failure. In colder months and in colder environments, the
temperature of the available water sources are typically less than
50.degree. F. (10.degree. C.) (even as low as below freezing) which
is generally an unsuitably cold temperature for the fracing
process. It is necessary to heat the available water to a
temperature (e.g., 40.degree. F. to 120.degree. F.+ (4.4.degree. C.
to 48.9.degree. C.+)) suitable for the fracing process prior to the
water and fracing fluids being pumped down hole.
There are common and known methods of providing heated water, which
require that prior to the fracing process, the source water is
pumped into numerous frac tanks and then the water in each
individual frac tank is circulated through a heating unit to raise
the temperature in the frac tank to a preset temperature required
for the chemical mixing of the frac. However, due to the time lapse
between heating (which is typically done the night before the
fracing operations) significant thermal loss occurs. Each tank has
to be heated to temperatures of for example 10-50.degree. F.
(5.6.degree. C. to 27.8.degree. C.) (often 20.degree. F. to
30.degree. F. (-11.1.degree. C. to 16.7.degree. C.)) higher than is
operationally necessary. For example, if the required temp is
70.degree. F. (21.degree. C.), then each tank would need to be
heated to at least 90.degree.-120.degree. F. (32.degree.
C.-48.9.degree. C.). The extensive over-heating is a substantial
expense and energy waste. The pumping of water to the frac tanks
and the use of heating units to heat the water in the frac tank are
well known in the industry. FIG. 5 is an example of a prior art
type configuration. There are multiple commercial businesses which
provide such services. The number of frac tanks can typically range
from 20-700 tanks (the average at the Marcellus Shale (located in
western New York extending south to Tennessee) is 500
tanks)--currently it costs around $500-2,000 per frac tank in a
typical fracing process (delivery, rental, cleaning, and
demobilization of the tank), so these frac tanks are a substantial
expense in the fracing process. Typically a substantial amount of
safety issues in fracing operations involves the handling of frac
tanks. One must heat the frac tanks to enough above the target
temperature to allow for thermal loss between heating and use.
Because normally heating of frac tanks occurs at night, this can be
10-50 degrees F. (5.6.degree. C. to 27.8.degree. C.), for example.
The amount of temperature above target will depend on local weather
conditions.
BRIEF SUMMARY OF THE INVENTION
The apparatus and method of the invention requires a water source,
pumps and piping that can provide continuous delivery of water,
such as up to about 100 barrels (11.9 kl) (sometimes as high as 150
(17.9 kl), and sometimes as low as 30-50 barrels (3.6-6.0 kl)) a
minute through a mixer or mixing manifold and to frac tanks.
As the water (usually cool or cold water) is pumped from its source
through the mixing manifold, a portion of the water volume (for
example 7 barrels (0.83 kl) a minute) is diverted through piping at
the manifold to and through a heating unit. This heating device is
preferably a mobile unit that can heat a smaller volume of water,
such as up to about 7 barrels (0.83 kl) per minute with a for
example 22 million BTU (23.2 billion Joules) heater (which
consistently heats to that capacity in all weather conditions,
regardless of ambient temperatures).
The heating unit creates an increase in the ambient water
temperature of the e.g., 7 bbls (0.83 kl) of the diverted water to
usually around 190-200.degree. F. (87.8-93.3.degree. C.) (and up to
240.degree. F. (116.degree. C.) in a pressurized piping system).
This heating is preferably done on a continuous flow basis (as
opposed to a batch process) with the heated water delivered through
piping back into the mixing manifold and continuously mixed into
the ambient water flow. The mixing of the superheated water with
the cooler water results in an increase in water temperature of
approximately 5.degree.-15.degree. F. (2.8-8.3.degree. C.) at a
rate of e.g. 100 barrels (bbls) (11.9 kl) per minute of continuous
pumping flow (per each heater unit). Lower flow rates (such as 20
bbls (2.4 kl) per minute) will increase the temperature faster to
result in a higher temperature rise. One can even run at 150 bbls
(17.9 kl) per minute, but the temperature rise per unit will be
lower.
To achieve higher water temperatures, multiple heating units (for
example 2-4 or even more) can be used to heat the water, all of
which is preferably done on a continuous flow basis. The moving
stream of uniformly heated water is preferably piped to a small
number of optional frac tank(s) which can be used as a safety
buffer between the water flow and the pumping operations, in the
case of a mechanical breakdown or operational problems.
The heating system with manifold can be designed for continuous
heating preferably up to about 100 bbls (11.9 kl) per minute (or
even more). To meet the required (target) temperature for the water
used in the fracing process (e.g., 40.degree. F. to 120.degree. F.+
(4.4.degree. C. to 48.9.degree. C.+), and often about
65.degree.-75.degree. F. (18.degree. C.-24.degree. C.), or
70.degree.-80.degree. F. (21.degree. C.-27.degree. C.)), the rate
of flow from the ambient source water can be adjusted to provide
greater or lesser volume and multiple, sequential mixing manifolds
and heater units can be added to the process.
The mixing manifold includes an intake opening and an outflow
opening allowing the source flowing water to pass through the
mixing manifold to the frac tanks. Between the intake opening and
the outflow opening, the mixing manifold has at least one cold
water diversion opening connected to piping to deliver a portion of
cold water flow to the heating unit. In the mixing manifold, a hot
water return opening is located downstream of the cold water
diversion opening, and this second opening, referred to as the hot
water return opening, allows the heated water into the mixing
manifold mixing with the cold water stream uniformly raising the
temperature of the water before the water reaches the frac tanks
(or the mixing tank or tanks if frac tanks are omitted).
In another embodiment, before pumping the heated water to a frac
tank (or the mixing tank or tanks if frac tanks are omitted), the
flow of the mixed heated water can again be passed through a second
mixer or second mixing manifold and a portion of the mixed heated
water is diverted to a second heating unit to heat that water to
200.degree. F. to 240.degree. F. (93.3.degree. C. to 116.degree.
C.), and that superheated water can be returned to the mixing
manifold for mixing with the continuously moving water stream at
about 100 bbls. (11.9 kl) per minute providing an additional
+10.degree. F. to +15.degree. F. (+5.6.degree. C. to +8.4.degree.
C.) uniform elevation of the temperature of the water flow. This
mixed and heated water can then be piped to optional frac tanks (if
used) and then to a mixing tank(s) for mixing with fracing
chemicals and then pumped down hole for use in the hydraulic
fracing process. If needed, multiple sequential heating units can
be attached along the pumping line to continuously raise the
temperature of the continuous flow of water to the required or
predetermined target temperature.
The mixing manifold can be any length or size of pipe or tank used
in the industry and the cold water diversion opening and the hot
water return opening can be configured and spaced in the mixing
manifold, or along the piping, in any useful manner to allow
superheated water to mix with continuously flowing source
water.
The mixing manifold or mixer can be for example 6-12 inches (15-30
cm) in diameter, such as a 10 inch (25 cm) diameter tubular member
or pipe with a length of approximately 2 to 3 feet (61-91 cm). The
pipe diameter and length can vary according to the requirements of
the pumping operations. The cold water diversion opening is
connected to a smaller pipe (such as a 3 inch (7.6 cm) pipe) that
is preferably attached to the mixing manifold at an angle (such as
approximately 45.degree.) forming a "y" with the mixing manifold
and the cold water diversion pipe. When heating water in Oklahoma,
some operators use 10-inch (25 cm) lines, some use 12-inch (30 cm)
lines. When heating water in Pennsylvania, some operators use
10-inch (25 cm) lines, and others use four to six 6-inch (10-15 cm)
lines.
Preferably, a raised rigid semi-circle shaped lip extends from the
backside of the cold water diversion opening into the mixing
manifold creating a partial blockage or impediment of the source
water flow stream causing a portion of the cold water flow stream
to divert into the cold water diversion opening and through the
piping to the heating unit. This protruding lip partially blocks
and obstructs the water flow inducing suction and flow into the
pipe to the heating unit. This partial blockage in the mixing
manifold also creates turbulence in the source water flow at and
beyond the cold water diversion opening that aids in mixing at the
superheated water inflow point. The lip can be a rigid metal
concave half circle having for example a 1/8 inch (0.32 cm) width
and 1.5 inch to 2 inch (3.81 cm to 5.08 cm) height at its highest
point with tapering to meet flush with the side of the mixing
manifold at the ends of the semi-circle of the lip; however, the
lip can be many shapes, sizes and locations in the mixing manifold
to induce suction and create turbulence in the mixing manifold.
The hot water return opening in the manifold for attachment of
piping for the superheated water is preferably located downstream
of the cold water diversion opening in the flowing source water in
the mixing manifold of the outflow pipe. The hot water return
opening for delivery of superheated water preferably likewise has a
lip extending into the stream of flowing water creating further
turbulence in the water resulting in greater mixing action of the
superheated water with the continuously flowing cold water creating
arise in temperature of the cold water as it passes along the
mixing manifold and through the piping to the frac tanks serving as
surge tanks (or directly to mixing tanks if there are no frac tanks
acting as surge tanks). This second lip located on the front side
or upstream side of the opening provides a partial blocking of the
flow of cold water aiding in the flow of the superheated water into
the mixing manifold. This lip adjacent to the opening on the hot
water return opening is optimally of the same size and shape of the
cold water diversion lip; however, this lip can also be utilized in
many shapes, sizes and locations in the mixing manifold to
partially block flow to facilitate hot water flow into the mixing
manifold and create additional turbulence in the mixing
manifold.
Additional mixing of the hot and cold water occurs beyond the
mixing manifold as the water flow is piped into and fills the
optional frac tanks if used and then piped as operations dictate to
mixing tanks to frac pumping units and to downhole. The heated
water is delivered and can be temporarily held in frac tanks or
surge tanks or pumped directly to mixing tanks without surge tanks.
The apparatus and process substantially reduce the number of
required frac tanks (or even eliminate the need for frac tanks). In
one embodiment of the described process, approximately six to eight
500 bbl (59.6 kl) frac tanks are utilized, which are used as a
safety buffer between the water flow and the pumping operations, in
the case of a mechanical breakdown or operational problems.
Suitable heating units can be commercially purchased through
manufacturers or fabricated. Exemplary manufacturers include Rush
Sales Company located in Odessa, Tex. (they produce Rush Frac Water
Heaters), and Chandler Manufacturing, Inc. in Wichita Falls, Tex.
(the diesel unit with six burners and a 22 million BTU (23.2
billion Joules) capacity is preferred) and Vita International.
Conventional heating trucks shown in FIG. 5 typically produce much
less than 20 million BTU (21.1 billion Joules). They could be used
in the system and method of the present invention, but more robust
heating units 12 (such as those produced by Chandler Manufacturing,
Inc.) capable of delivery of at least 15 million BTU (15.8 billion
Joules), preferably up to 25 million BTU (26.4 billion Joules)
(e.g. 22 million BTU (23.2 billion Joules) or more) are preferred.
The piping, pumps and frac tanks are all readily available from
numerous suppliers and contractors in the industry.
There are numerous other conceivable arrangements and
configurations of the inflow and outflow of the cold water and hot
water and piping in the mixing manifold, including parallel pumping
of cold and hot water inflow and use of secondary source of water
to the heaters independent of the primary source water passing
through the mixing manifold.
The method of this invention can include some or all of the
following steps. These steps can be in the following order.
1) Establish a flow of source water at between about 20-150+ bbls
(2.4-17.9+ kl) (more typically 60 to 100 bbls (7.2 to 11.9 kl)) per
minute through piping to a piping manifold or mixer, which diverts
a portion of the source water to one or more heating units,
2) The superheated water returns to the continuous flowing source
water to meet the required or target temperatures, and
3) The warmed water (e.g. 60.degree.-120.degree. F.+
(16-48.9.degree. C.+), typically 65.degree.-80.degree. F.
(18-27.degree. C.)) sent to the mixing tanks for chemical additives
and the eventual fracing process.
Examples of chemicals that can be added to the water include:
bentonite gel and other chemicals used by such frac operators as
Schlumberger, Halliburton, and BJ Services. Typically proppants
(such as sand, ceramic beads, bauxite, or others) are mixed with
the water before the water is injected downhole. The proppants help
to keep the fractures which are produced open. The proppants can be
for example any which are used by such frac operators as
Schlumberger, Halliburton, and BJ Services.
In general, it is possible to use water of a lower temperature if
one uses more chemicals. For example, while normally one might wish
to use water of 40.degree.-120.degree. F. (4.4.degree.
C.-48.9.degree. C.) in a particular fracing process at a particular
location ("slick water frac" refers to a process where less
chemicals are used (or sometimes even no chemicals)--it uses
turbulent flow with a lot of pressure--proppants are used with all
fracing processes--typically one can carry more (sometimes up to
two to three times as much) proppant in a slick water frac compared
to a gel frac), one could instead use water at a lower temperature
of 60.degree.-120.degree. F. (16.degree. C.-48.9.degree. C.) ("gel
frac" refers to this process where more chemicals are used--gel and
proppant). Examples of amounts of water used in a fracing process
are 30,000 barrels to 350,000 barrels (3,577-41,734 kl), though one
might use as few as 10,000 barrels (1,192 kl) to over one million
barrels (119,240 kl) (this larger amount may cover multiple wells,
for example). Higher water temperature can sometimes result in
lower chemical usage. Some of the wells currently are approaching 1
million pounds (453,592 kg) of sand as a proppant with 350,000
barrels (41,734 kl) of water.
Through testing in cold temperatures, the inventor has learned that
heating water from around freezing to about 40 degrees F.
(4.4.degree. C.) takes a great degree of heat. One might need more
heaters when heating water from near freezing, or one might
initially preheat some water in frac tanks (e.g., 3 or 4 up to 50
or 100 frac tanks) to add heat one needs to move the temperature of
the water up from near freezing to about 40 degrees F. (4.4.degree.
C.). One could also add heating in a water pit itself to help raise
the water temperature to around 40 degrees F. (4.4.degree. C.).
Also, when a water source contains ice, it is best to withdraw only
liquid water, and no ice, from the water source. Otherwise, a good
amount of heat can be lost melting the ice.
Preferably one places one or two units near the water source and
another unit near the fracing pumps. It appears that there is
additional heating in the pipeline (due to friction, the inventor
believes) of perhaps a degree or two F. (0.6-1.1.degree. C.) when
the water travels about a mile (1.61 km).
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
For a further understanding of the nature, objects, and advantages
of the present invention, reference should be had to the following
detailed description, read in conjunction with the following
drawings, wherein like reference numerals denote like elements and
wherein:
The invention and features of the invention is shown and disclosed
by the following Figures and photographs representing informal
drawings.
FIG. 1 is a partial perspective view of a preferred embodiment of
the apparatus of the present invention;
FIG. 2 is a sectional view taken along lines 2-2 of FIG. 1;
FIG. 3 is a schematic diagram of a preferred embodiment of the
apparatus of the present invention and illustrating the method of
the present invention;
FIG. 4 is a schematic diagram of another preferred embodiment of
the apparatus of the present invention and illustrating a method of
the present invention;
FIG. 5 is a schematic diagram of a prior art oil well frac pumping
system;
FIG. 6 is a schematic diagram of a preferred embodiment of the
apparatus of the present invention;
FIG. 7 is a schematic diagram of an alternative embodiment of the
apparatus of the present invention;
FIG. 8 is a schematic diagram of another alternative embodiment of
the apparatus of the present invention;
FIG. 9 is a schematic diagram of another alternative embodiment of
the apparatus of the present invention;
FIG. 10 is a schematic diagram of another alternative embodiment of
the apparatus of the present invention;
FIG. 11 is a schematic diagram of another alternative embodiment of
the apparatus of the present invention; and
FIG. 12 is a schematic diagram of another alternative embodiment of
the apparatus of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1-4 and 6-12 show preferred embodiments of the apparatus of
the present invention, designated generally by the numeral 10 in
FIGS. 3 and 6. Alternate embodiments are designated by the numeral
110 in FIG. 4, by the numeral 210 in FIG. 7, by the numeral 310 in
FIG. 8, by the numeral 410 in FIG. 9, by the numeral 510 in FIG.
10, by the numeral 610 in FIG. 11, and by the numeral 710 in FIG.
12. In FIG. 6, a water source 11 can be a reservoir, lake or other
source of water.
Mobile heater apparatus 12 is used to super heat water for use in
frac operations in an oil well. In general, such frac operations
can be seen in U.S. Pat. No. 4,137,182, hereby incorporated herein
by reference.
Mobile heater 12 is a transportable heating apparatus and includes
a truck 13 and a trailer 14. Trailer 14 carries a heating vessel 15
which can be, for example, a tank or piping that holds water and
that can be heated with electrical or other heating elements or
with propane or preferably diesel burners. Water to be injected
into an oil well 16 as part of a hydraulic fracturing operation
include very hot water that is heated by mobile heater 12 and
ambient water that is received from water source 11.
A pumping apparatus 17 which can include a truck 13 and trailer 18
pumps the prepared water (water plus selected chemical (optional)
and proppant) into the well 16. Water from source 11 flows in
flowline 19 to mixer 20. Mixer or mixing manifold 20 can be seen in
more detail in FIGS. 1 and 2. Mixer 20 receives ambient temperature
water from water source 11 and mixes that ambient temperature water
with very hot water that is heated in vessel 15 of mobile heater
12.
The details of mixer 20 are seen in FIGS. 1 and 2. The mixer 20 has
a tubular or cylindrically-shaped body 21 defined by a wall 22
which surrounds bore 23. Tubular body 21 has a first inlet 26 in a
first inlet end portion 24, and a first outlet 27 in an outlet end
portion 25. The bore 23 communicates with flow inlet 26 and flow
outlet 27. Arrows 28, 29 illustrate the direction of flow of water
in body 21 as shown in FIG. 2. Curved arrows 30 in FIG. 2
illustrate turbulent flow that occurs for ensuring that heated
water and ambient temperature water thoroughly mix.
A pair of conduits are connected to tubular body 21. These include
conduit 31 and conduit 32. Conduit 31 is a second outlet and
removes ambient temperature water from the bore 23 of tubular body
21. Conduit 32 is a second inlet and injects heated water into bore
23 of tubular body 21 and downstream of conduit 31. In this
fashion, conduit 31 does not discharge any heated water from bore
23 of tubular body 21. Rather, the water leaving bore 23 of tubular
body 21 via conduit 31 is ambient temperature water. This discharge
of ambient temperature from tubular body 21 of mixer 20 is
illustrated by arrows 39 in FIG. 2.
Each of the conduits 31, 32 has a bore. The conduit 31 has bore 33.
The conduit 32 has bore 34. Each of the conduits 31, 32 has an
inner end portion and an outer end portion. Conduit 31 has inner
end portion 35 and outer end portion 36. Conduit 32 has inner end
portion 37 and outer end portion 38. Each of the inner end portions
35, 37 occupies a position within bore 23 of tubular body 21 as
shown in FIG. 2. In this fashion, bore 33 of conduit 31 occupies a
part of bore 23 of tubular body 21. Similarly, fluid discharging
from bore 34 of conduit 32 is discharged directly into the bore 23
of tubular body 21. The arrows 40 in FIG. 2 illustrate the
discharge of heated water via conduit 32 into bore 23 of tubular
body 21.
While the angle of the longitudinal axis of bore 33 of conduit 31
and the angle of the longitudinal axis of bore 34 of conduit 32 in
relation to the longitudinal axis of bore 23 of tubular body 21 are
shown to be about 45 degrees, those angles could vary from 0 to 90
degrees, and they need not be the same.
As can be seen in FIG. 2, first inlet 26 is upstream of second
outlet 31, which is upstream of second inlet 32, which itself is
upstream of first outlet 27.
In FIG. 6, flow lines 41 and 42 are used to transfer water in
between mobile heater 12 and mixer 20. The flow line 41 receives
water from conduit 31, a second outlet, which is ambient
temperature water and transports that ambient temperature water to
vessel 15 of heater 12. After water has been heated in vessel 15,
it is transported via flow line 42 to conduit 32, a second inlet,
of mixer 20. It should be understood that the flow of fluids from
flow line 41 to and through vessel 15 of heater 12 and then to flow
line 42 can be a continuous process. As an example, the flow of
ambient temperature water in flow line 19 can be about 20-150 bbls
(2.4-17.9 kl) per minute, and typically around 60-100 barrels
(7.2-11.9 kl) per minute. The flow rate in flow lines 41 and 42 can
be for example a continuous 7 barrels (0.83 kl) per minute.
The temperature in the super heated flow line 42 can be in excess
of 200.degree. F. (93.3.degree. C.) and in excess of 240.degree. F.
(116.degree. C.) if flow line 42 is pressurized. Flow lines 43 and
44 illustrate the transfer of warmed water from mixing tanks or
downhole tanks 46 to pumping apparatus 17 and then into the well 16
for use in frac operations. In FIG. 6, surge tanks 45 can
optionally be used downstream of mixer 20 and upstream of mixing
tanks 46.
To achieve higher water temperatures, multiple heating units 12 can
be used to heat the water all of which is done on a continuous flow
basis as shown in FIG. 4. The moving stream of uniformly heated
water can be piped to surge tank(s) which can be used as a safety
buffer between the water flow and the pumping operations, in the
case of a mechanical breakdown or operational problems.
In FIG. 4, a joint of pipe 47 (commercially available) can be
placed in between the two mixers 20 as shown. In FIG. 4, the flow
of the mixed heated water can be passed through a second mixer or
second mixing manifold 20 and a portion of the mixed heated water
is diverted to a second heating unit 12 to heat that water to for
example between about 200.degree. F. to 240.degree. F.
(93.3.degree. C. to 116.degree. C.). That superheated water can be
returned to the mixing manifold 20 for mixing with the continuously
moving water stream providing an additional +10.degree. F. to
+15.degree. F. (+5.6.degree. C. to +8.4.degree. C.) uniform
elevation of the temperature of the water flow. This mixed and
heated water can then be piped to mixing tanks 46 for mixing with
any selected hydraulic fracturing chemicals and then pumped down
hole for use in the hydraulic fracturing process. If needed,
multiple sequential heating units 12 (and mixers 20) can be
attached along the pumping line to continuously raise the
temperature of the continuous flow of water to a required or target
temperature. The mixers 20 can be connected in series (as in FIG.
4) or in parallel or a combination of series and parallel (as in
FIGS. 10 and 12).
In FIG. 7 (an alternate configuration), the surge tanks have been
eliminated. The mixing tanks 46 can be used to mix any selected
chemical and proppant or proppants with the water that has been
discharged from mixer 20 and that is ready for use in hydraulic
fracturing operation in the well 16.
Conventional heater trucks 112 shown in FIG. 5 typically produce
much less than 20 million BTU (21.1 billion Joules). They could be
used in the system and method of the present invention, but more
robust heating units 12 (such as those produced by Chandler
Manufacturing, Inc. in Wichita Falls, Tex.) capable of delivery of
22 million BTU (23.2 billion Joules) or more are preferred.
Especially preferred are diesel powered heater units commercially
available from Chandler Manufacturing, Inc. in which water flows
through a series of metal coils, and there are six burners which
heat the coils. An example of such a heater unit can be seen at
www.chandlermfg.com/item.php?pid=34 and is identified as an
oil-fired frac water heater (and shown in US Patent Publication no.
US 2010/0000508). However, other heater units which can quickly
heat large quantities of water can be used. The diesel powered
units are preferred because in colder environments propane tends to
liquify and not heat as effectively. Preferably one can run 70-100
barrels (8.3-11.9 kl) per minute per heating truck of the present
invention while getting a temperature rise of at least about 15
degrees Fahrenheit (8.4.degree. C.).
Through testing in cold temperatures, the inventor has learned that
heating water from around freezing to about 40 degrees F.
(4.4.degree. C.) takes a great degree of heat. One might need more
heaters 12 when heating water from near freezing, or one might
initially preheat some water in additional frac tanks (e.g., 3 or 4
up to 50 or 100 frac tanks) to add heat one needs to move the
temperature of the water up from near freezing to about 40 degrees
F. (4.4.degree. C.). One could also add heating in a water pit
itself (e.g., when the water source 11 is a pond) to help raise the
water temperature to around 40 or 45 degrees F. (4.4 or 7.2.degree.
C.) (there will be radiant heat loss from the water pit, so
typically one would not want to heat the water in the pit much
above 40 to 45 degrees F. (4.4 to 7.2.degree. C.)) before further
heating the water with the heating system of present invention
shown in FIGS. 3 and 4, for example. The heating in the water pit
could be done with, for example, a heater or heaters 12 as shown in
FIGS. 3 and 4 that circulate water through hoses 41 and 42 to and
from the water pit.
Also, while typically water freezes at 32 degrees F. (0.degree.
C.), flowing water or water with various substances can sometimes
cool below 32 degrees F. (0.degree. C.) without freezing. Thus,
sometimes the present invention might start processing water which
is below 32 degrees F. (0.degree. C.). Also, sometimes the source
water might have ice in it, but it can still be used if the water
with ice can flow through mixer 20. However, it is preferred to
avoid pulling ice into the intake, as considerable heat can be lost
when melting the ice.
Surge or pivot tanks 45 are preferably upright circular tanks where
the water flows in and out (similar to or the same as the mixing
tanks 46 shown in FIG. 6). The agitation which occurs in the surge
tanks 45 is helpful, and seem to add heat to the water (better
mixing seems to occur as well, so even if surge or pivot tanks 45
are not needed for surge, one might want to use 2-20 of these
anyway).
Manifolding among multiple surge or pivot tanks can be done to
balance heat. Pivot or surge tanks 45 could be shaped like mixing
tanks 46. Preferably the heated water flows through the surge tanks
(as shown in FIG. 10, where mixing tanks 46 are acting as surge
tanks). The surge tanks provide a buffer in the event of some
breakdown or other problem making it difficult to produce heater
water. During the breakdown or other problem, heated water from the
surge tanks can be routed to the mixing tanks, even though no
heated water will be refilling the surge tanks. Preferably, either
enough surge tanks are provided that no interruption in fracing
occurs during a breakdown or other problem causing an interruption
in heated water production, or enough surge tanks are provided that
an orderly shutdown of fracing occurs during a breakdown or other
problem causing an interruption in heated water production.
Typically surge tanks hold around 480-500 barrels (57.2-59.6 kl) of
heated water per tank.
Though pumps and valves are not shown in the drawings, appropriate
pumps and valves are provided to direct water as desired, and one
of ordinary skill in the art will be able to determine where to
place such pumps and valves to achieve desired water flow. Water
lines can be manifolded together and several lines could feed and
emanate from a single heating truck.
Flow rates can be 100 barrels (11.9 kl) per minute (though this
could be higher or lower) and with the preferred heater trucks of
the present invention, there will preferably be around a 15 degree
F. (8.4.degree. C.) increase in temperature at 100 barrels (11.9
kl) per minute (for one truck).
The current normal target water temperature is 70-90 degrees F.
(21.1-32.2.degree. C.) (but it could be higher). Overheating of the
water is not needed (as one must do when heating tanks) as the heat
loss (if any) using the on-line heating method of the present
invention is typically minimal.
Maintenance of trucks used in the present invention includes
chemical (e.g., hydrochloric acid) washing of the coils to keep
heat transfer times low (otherwise there can be buildup on the
coils which impedes heat transfer).
Probably a vertical, round tank (such as mixing tank 46) will work
better for mixing hot and cold water to get a more uniform
temperature of water to use in fracing.
FIG. 8 is similar to FIG. 7, but apparatus 310 shown therein
includes a mixing tank 46 instead of the manifold 20 shown in FIG.
7 (anything that could cause turbulence could be used instead of
the manifold 20 shown in FIG. 1, though the manifold 20 is
preferred as it is a relatively simple and compact mixing device).
Water drawn from water source 11 travels through flow line 19 and
first inlet 56 into mixing tank 46, where some of the water is
drawn off through second outlet 61 and line 41 into mobile heater
12, then back through flow line 42 and second inlet 62 into mixing
tank 46, where it then continues to flow through first outlet 57
and flow line 19 to mixing tanks 46 which are near frac pumping
apparatus 17. From there the water flows as in FIG. 7. It is
believed that better mixing of water occurs in tank 46 when first
inlet 56 is near the bottom of tank 46, first outlet 57 is near the
top of tank 46, and second inlet 62 is somewhere in between. Also,
it is believed that better mixing will occur if mixing tank 46 is a
vertical cylindrical tank as shown in the drawings.
FIG. 9 is similar to FIG. 8, but apparatus 410 shown therein
includes a half manifold 120 and a mixing tank 46 instead of the
manifold 20 shown in FIG. 1. As indicated in FIG. 9, water at the
temperature of the water source 11 flows through half manifold 120,
where some of the water is diverted out through second outlet
(conduit) 31 of half manifold 120 into flow line 41 and to heater
12, then out through flow line 42 into second inlet 62 of mixing
tank 46. The heated water from line 42 mixes in mixing tank 46 with
the water which is at the temperature of water source 11 which
enters tank 46 at first inlet 56. The water then flows out through
first outlet 57 through flow line 19 to mixing tanks 46 which are
near frac pumping apparatus 17. From there the water flows as in
FIG. 7.
FIG. 10 shows apparatus 510, which includes three mobile heaters 12
with three manifolds 20, two mobile heaters 12 in parallel with one
another and located near the water source 11, and one mobile heater
12 closer to the frac pumping apparatus 17. There are three surge
tanks 46 in series with one of the mobile heaters 12, though these
surge tanks 46 could be in series with both mobile heaters 12 which
are in parallel to one another, or they could be in series with all
three mobile heaters 12 shown in FIG. 10. Further, there could be
as few as none or one surge tank 46 to as many as considered
prudent by the operator, which could be for example three or four
up to 50 or 100 mixing tanks 46 (or even more). Flow of water
through manifolds 20, heaters 12, and surge tanks 46 is as in prior
figures.
FIG. 11 shows apparatus 610, which includes two mobile heaters 12
connected directly to the source water 11 (a pond) with the water
being withdrawn from and returned to the pond. There are also three
mobile heaters 12, each connected to a mixing tank 46, heating
water in the mixing tanks 46. Further, there could be as few as
none or one surge tank 46 and associated mobile heaters 12 to as
many as considered prudent by the operator, which could be for
example three or four up to 50 or 100 mixing tanks 46 with
associated mobile heaters 12 (or even more).
FIG. 12 is similar to FIG. 11, but in FIG. 12 apparatus 710 differs
from apparatus 610 in that one truck has moved from the pond 11 and
is heating the water as it runs through the flow line 19. FIG. 12
shows three additional mixing tanks 46 in series with pipe 19 and
acting as surge tanks. As in FIG. 11, there are also three mobile
heaters 12, each connected to a mixing tank 46, heating water in
the mixing tanks 46. These mixing tanks 46 are in series with one
another in a flow line 119 which runs parallel to flow line 19 and
then feeds into flow line 19. Further, there could be as few as
none or one surge tank 46 and associated mobile heaters 12 to as
many as considered prudent by the operator, which could be for
example three or four up to 50 or 100 mixing tanks 46 with
associated mobile heaters 12 (or even more).
There is a huge lake (Lake Sakakawea) in the middle of western
North Dakota. Fracing operations were making a tremendous strain on
groundwater. Now it is expected that water will be pulled from Lake
Sakakawea with permits currently in process. It is believed that
companies will soon pump water out of Lake Sakakawea and put it
into insulated tanks, where it will be heated in the tanks. The
water will then be taken via insulated trucks to a well site where
fracing operations occur. The apparatus of the present invention
can heat water as it is pumped from the lake into the tanks (and it
can continue to heat the water once it is in the tanks). This
method can occur in other areas as well.
The following is a list of parts and materials suitable for use in
the present invention:
TABLE-US-00001 PARTS LIST Parts Number Description 10 hydraulic
fracturing pumping system 11 water source 12 mobile heater
apparatus 13 truck 14 trailer 15 vessel 16 oil and/or gas well 17
frac pumping apparatus 18 trailer 19 flow line 20 mixer 21
tubular/cylindrically-shaped body 22 wall 23 bore 24 inlet end
portion 25 outlet end portion 26 inlet 27 outlet 28 arrow 29 arrow
30 curved arrow 31 conduit (second outlet) 32 conduit (second
inlet) 33 bore 34 bore 35 inner end portion 36 outer end portion 37
inner end portion 38 outer end portion 39 arrow 40 arrow 41 flow
line 42 flow line 43 flow line 44 flow line 45 surge tank 46 mixing
tank or downhole tank or surge tank 47 joint of pipe 56 inlet
(first) of mixing tank 46 57 outlet (first) of mixing tank 46 61
second outlet of mixing tank 46 62 second inlet of mixing tank 46
110 hydraulic fracturing pumping system 112 prior art mobile
heating truck 119 flow line 120 half manifold 210 hydraulic
fracturing pumping system 310 hydraulic fracturing pumping system
410 hydraulic fracturing pumping system 510 hydraulic fracturing
pumping system 610 hydraulic fracturing pumping system 710
hydraulic fracturing pumping system
All measurements disclosed herein are at standard temperature and
pressure, at sea level on Earth, unless indicated otherwise.
The foregoing embodiments are presented by way of example only; the
scope of the present invention is to be limited only by the
following claims.
* * * * *
References